From patchwork Thu Jul 11 12:09:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fiona Ebner X-Patchwork-Id: 13730643 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 31F4DC3DA49 for ; Thu, 11 Jul 2024 12:10:34 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sRscF-0001gv-7k; Thu, 11 Jul 2024 08:09:39 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sRsc9-0001Ol-7O; Thu, 11 Jul 2024 08:09:33 -0400 Received: from proxmox-new.maurer-it.com ([94.136.29.106]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sRsbz-0002s0-91; Thu, 11 Jul 2024 08:09:32 -0400 Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 0DCD747347; Thu, 11 Jul 2024 14:09:20 +0200 (CEST) From: Fiona Ebner To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, armbru@redhat.com, eblake@redhat.com, hreitz@redhat.com, kwolf@redhat.com, vsementsov@yandex-team.ru, jsnow@redhat.com Subject: [PATCH v3 1/2] copy-before-write: allow specifying minimum cluster size Date: Thu, 11 Jul 2024 14:09:14 +0200 Message-Id: <20240711120915.310243-2-f.ebner@proxmox.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240711120915.310243-1-f.ebner@proxmox.com> References: <20240711120915.310243-1-f.ebner@proxmox.com> MIME-Version: 1.0 Received-SPF: pass client-ip=94.136.29.106; envelope-from=f.ebner@proxmox.com; helo=proxmox-new.maurer-it.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org In the context of backup fleecing, discarding the source will not work when the fleecing image has a larger granularity than the one used for block-copy operations (can happen if the backup target has smaller cluster size), because cbw_co_pdiscard_snapshot() will align down the discard requests and thus effectively ignore then. To make @discard-source work in such a scenario, allow specifying the minimum cluster size used for block-copy operations and thus in particular also the granularity for discard requests to the source. The type 'size' (corresponding to uint64_t in C) is used in QAPI to rule out negative inputs and for consistency with already existing @cluster-size parameters. Since block_copy_calculate_cluster_size() uses int64_t for its result, a check that the input is not too large is added in block_copy_state_new() before calling it. The calculation in block_copy_calculate_cluster_size() is done in the target int64_t type. Suggested-by: Vladimir Sementsov-Ogievskiy Acked-by: Markus Armbruster (QAPI schema) Signed-off-by: Fiona Ebner Reviewed-by: Vladimir Sementsov-Ogievskiy --- Changes in v3: * Pass min_cluster_size option directly without checking has_min_cluster_size, because the default is 0 anyways. * Calculate maximum of passed-in argument and default once at the beginning of block_copy_calculate_cluster_size() * Update warning message to reflect actual value used * Use PRI{i,u}64 macros block/block-copy.c | 36 ++++++++++++++++++++++++++---------- block/copy-before-write.c | 5 ++++- include/block/block-copy.h | 1 + qapi/block-core.json | 8 +++++++- 4 files changed, 38 insertions(+), 12 deletions(-) diff --git a/block/block-copy.c b/block/block-copy.c index 7e3b378528..59bee538eb 100644 --- a/block/block-copy.c +++ b/block/block-copy.c @@ -310,6 +310,7 @@ void block_copy_set_copy_opts(BlockCopyState *s, bool use_copy_range, } static int64_t block_copy_calculate_cluster_size(BlockDriverState *target, + int64_t min_cluster_size, Error **errp) { int ret; @@ -319,6 +320,9 @@ static int64_t block_copy_calculate_cluster_size(BlockDriverState *target, GLOBAL_STATE_CODE(); GRAPH_RDLOCK_GUARD_MAINLOOP(); + min_cluster_size = MAX(min_cluster_size, + (int64_t)BLOCK_COPY_CLUSTER_SIZE_DEFAULT); + target_does_cow = bdrv_backing_chain_next(target); /* @@ -329,13 +333,13 @@ static int64_t block_copy_calculate_cluster_size(BlockDriverState *target, ret = bdrv_get_info(target, &bdi); if (ret == -ENOTSUP && !target_does_cow) { /* Cluster size is not defined */ - warn_report("The target block device doesn't provide " - "information about the block size and it doesn't have a " - "backing file. The default block size of %u bytes is " - "used. If the actual block size of the target exceeds " - "this default, the backup may be unusable", - BLOCK_COPY_CLUSTER_SIZE_DEFAULT); - return BLOCK_COPY_CLUSTER_SIZE_DEFAULT; + warn_report("The target block device doesn't provide information about " + "the block size and it doesn't have a backing file. The " + "(default) block size of %" PRIi64 " bytes is used. If the " + "actual block size of the target exceeds this value, the " + "backup may be unusable", + min_cluster_size); + return min_cluster_size; } else if (ret < 0 && !target_does_cow) { error_setg_errno(errp, -ret, "Couldn't determine the cluster size of the target image, " @@ -345,16 +349,17 @@ static int64_t block_copy_calculate_cluster_size(BlockDriverState *target, return ret; } else if (ret < 0 && target_does_cow) { /* Not fatal; just trudge on ahead. */ - return BLOCK_COPY_CLUSTER_SIZE_DEFAULT; + return min_cluster_size; } - return MAX(BLOCK_COPY_CLUSTER_SIZE_DEFAULT, bdi.cluster_size); + return MAX(min_cluster_size, bdi.cluster_size); } BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target, BlockDriverState *copy_bitmap_bs, const BdrvDirtyBitmap *bitmap, bool discard_source, + uint64_t min_cluster_size, Error **errp) { ERRP_GUARD(); @@ -365,7 +370,18 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target, GLOBAL_STATE_CODE(); - cluster_size = block_copy_calculate_cluster_size(target->bs, errp); + if (min_cluster_size > INT64_MAX) { + error_setg(errp, "min-cluster-size too large: %" PRIu64 " > %" PRIi64, + min_cluster_size, INT64_MAX); + return NULL; + } else if (min_cluster_size && !is_power_of_2(min_cluster_size)) { + error_setg(errp, "min-cluster-size needs to be a power of 2"); + return NULL; + } + + cluster_size = block_copy_calculate_cluster_size(target->bs, + (int64_t)min_cluster_size, + errp); if (cluster_size < 0) { return NULL; } diff --git a/block/copy-before-write.c b/block/copy-before-write.c index 853e01a1eb..a919b1f41b 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -417,6 +417,7 @@ static BlockdevOptions *cbw_parse_options(QDict *options, Error **errp) qdict_extract_subqdict(options, NULL, "bitmap"); qdict_del(options, "on-cbw-error"); qdict_del(options, "cbw-timeout"); + qdict_del(options, "min-cluster-size"); out: visit_free(v); @@ -476,8 +477,10 @@ static int cbw_open(BlockDriverState *bs, QDict *options, int flags, bs->file->bs->supported_zero_flags); s->discard_source = flags & BDRV_O_CBW_DISCARD_SOURCE; + s->bcs = block_copy_state_new(bs->file, s->target, bs, bitmap, - flags & BDRV_O_CBW_DISCARD_SOURCE, errp); + flags & BDRV_O_CBW_DISCARD_SOURCE, + opts->min_cluster_size, errp); if (!s->bcs) { error_prepend(errp, "Cannot create block-copy-state: "); return -EINVAL; diff --git a/include/block/block-copy.h b/include/block/block-copy.h index bdc703bacd..dd5cc82f3b 100644 --- a/include/block/block-copy.h +++ b/include/block/block-copy.h @@ -28,6 +28,7 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target, BlockDriverState *copy_bitmap_bs, const BdrvDirtyBitmap *bitmap, bool discard_source, + uint64_t min_cluster_size, Error **errp); /* Function should be called prior any actual copy request */ diff --git a/qapi/block-core.json b/qapi/block-core.json index 096bdbe0aa..80e32db8aa 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -4638,12 +4638,18 @@ # @on-cbw-error parameter will decide how this failure is handled. # Default 0. (Since 7.1) # +# @min-cluster-size: Minimum size of blocks used by copy-before-write +# operations. Has to be a power of 2. No effect if smaller than +# the maximum of the target's cluster size and 64 KiB. Default 0. +# (Since 9.1) +# # Since: 6.2 ## { 'struct': 'BlockdevOptionsCbw', 'base': 'BlockdevOptionsGenericFormat', 'data': { 'target': 'BlockdevRef', '*bitmap': 'BlockDirtyBitmap', - '*on-cbw-error': 'OnCbwError', '*cbw-timeout': 'uint32' } } + '*on-cbw-error': 'OnCbwError', '*cbw-timeout': 'uint32', + '*min-cluster-size': 'size' } } ## # @BlockdevOptions: From patchwork Thu Jul 11 12:09:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fiona Ebner X-Patchwork-Id: 13730644 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3F5BDC3DA41 for ; Thu, 11 Jul 2024 12:11:06 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sRscB-0001ST-Gu; Thu, 11 Jul 2024 08:09:35 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sRsc9-0001Oi-40; Thu, 11 Jul 2024 08:09:33 -0400 Received: from proxmox-new.maurer-it.com ([94.136.29.106]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sRsbz-0002sP-AD; Thu, 11 Jul 2024 08:09:32 -0400 Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id C4DD3409F2; Thu, 11 Jul 2024 14:09:19 +0200 (CEST) From: Fiona Ebner To: qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, armbru@redhat.com, eblake@redhat.com, hreitz@redhat.com, kwolf@redhat.com, vsementsov@yandex-team.ru, jsnow@redhat.com Subject: [PATCH v3 2/2] backup: add minimum cluster size to performance options Date: Thu, 11 Jul 2024 14:09:15 +0200 Message-Id: <20240711120915.310243-3-f.ebner@proxmox.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240711120915.310243-1-f.ebner@proxmox.com> References: <20240711120915.310243-1-f.ebner@proxmox.com> MIME-Version: 1.0 Received-SPF: pass client-ip=94.136.29.106; envelope-from=f.ebner@proxmox.com; helo=proxmox-new.maurer-it.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org In the context of backup fleecing, discarding the source will not work when the fleecing image has a larger granularity than the one used for block-copy operations (can happen if the backup target has smaller cluster size), because cbw_co_pdiscard_snapshot() will align down the discard requests and thus effectively ignore then. To make @discard-source work in such a scenario, allow specifying the minimum cluster size used for block-copy operations and thus in particular also the granularity for discard requests to the source. Suggested-by: Vladimir Sementsov-Ogievskiy Acked-by: Markus Armbruster (QAPI schema) Signed-off-by: Fiona Ebner Reviewed-by: Vladimir Sementsov-Ogievskiy --- Changes in v3: * Use PRI{i,u}64 macros * Do not leak qdict in error case block/backup.c | 2 +- block/copy-before-write.c | 9 +++++++++ block/copy-before-write.h | 1 + blockdev.c | 3 +++ qapi/block-core.json | 9 +++++++-- 5 files changed, 21 insertions(+), 3 deletions(-) diff --git a/block/backup.c b/block/backup.c index 3dd2e229d2..a1292c01ec 100644 --- a/block/backup.c +++ b/block/backup.c @@ -458,7 +458,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, } cbw = bdrv_cbw_append(bs, target, filter_node_name, discard_source, - &bcs, errp); + perf->min_cluster_size, &bcs, errp); if (!cbw) { goto error; } diff --git a/block/copy-before-write.c b/block/copy-before-write.c index a919b1f41b..e835987e52 100644 --- a/block/copy-before-write.c +++ b/block/copy-before-write.c @@ -548,6 +548,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, BlockDriverState *target, const char *filter_node_name, bool discard_source, + uint64_t min_cluster_size, BlockCopyState **bcs, Error **errp) { @@ -567,6 +568,14 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, qdict_put_str(opts, "file", bdrv_get_node_name(source)); qdict_put_str(opts, "target", bdrv_get_node_name(target)); + if (min_cluster_size > INT64_MAX) { + error_setg(errp, "min-cluster-size too large: %" PRIu64 " > %" PRIi64, + min_cluster_size, INT64_MAX); + qobject_unref(opts); + return NULL; + } + qdict_put_int(opts, "min-cluster-size", (int64_t)min_cluster_size); + top = bdrv_insert_node(source, opts, flags, errp); if (!top) { return NULL; diff --git a/block/copy-before-write.h b/block/copy-before-write.h index 01af0cd3c4..2a5d4ba693 100644 --- a/block/copy-before-write.h +++ b/block/copy-before-write.h @@ -40,6 +40,7 @@ BlockDriverState *bdrv_cbw_append(BlockDriverState *source, BlockDriverState *target, const char *filter_node_name, bool discard_source, + uint64_t min_cluster_size, BlockCopyState **bcs, Error **errp); void bdrv_cbw_drop(BlockDriverState *bs); diff --git a/blockdev.c b/blockdev.c index 835064ed03..6740663fda 100644 --- a/blockdev.c +++ b/blockdev.c @@ -2655,6 +2655,9 @@ static BlockJob *do_backup_common(BackupCommon *backup, if (backup->x_perf->has_max_chunk) { perf.max_chunk = backup->x_perf->max_chunk; } + if (backup->x_perf->has_min_cluster_size) { + perf.min_cluster_size = backup->x_perf->min_cluster_size; + } } if ((backup->sync == MIRROR_SYNC_MODE_BITMAP) || diff --git a/qapi/block-core.json b/qapi/block-core.json index 80e32db8aa..9a54bfb15f 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -1551,11 +1551,16 @@ # it should not be less than job cluster size which is calculated # as maximum of target image cluster size and 64k. Default 0. # +# @min-cluster-size: Minimum size of blocks used by copy-before-write +# and background copy operations. Has to be a power of 2. No +# effect if smaller than the maximum of the target's cluster size +# and 64 KiB. Default 0. (Since 9.1) +# # Since: 6.0 ## { 'struct': 'BackupPerf', - 'data': { '*use-copy-range': 'bool', - '*max-workers': 'int', '*max-chunk': 'int64' } } + 'data': { '*use-copy-range': 'bool', '*max-workers': 'int', + '*max-chunk': 'int64', '*min-cluster-size': 'size' } } ## # @BackupCommon: